The dinner suit, dinner jacket or black tie is semi formal men’s attire for social events after 6pm.
It comprises a black or midnight blue two or three piece suit distinguished by satin jacket lapels and similar stripes along the outseam of the trousers. The dinner suit is worn with a white dress shirt with standing or turndown collar and cuff links, a black bow tie, typically a cummerbund or an evening waist coat and black patent leather dress shoes.
It was introduced by the Prince of Wales in 1865.
He once invited a wealthy New Yorker acquaintance to his estate who asked for the dress code. The future king sent him to his tailor to have a dinner suit made.
This man returned to his home in Tuxedo Park, New York to great acclaim and Americans started calling the dinner suit a tuxedo.
Informed British, Irish, Canadian, Australian and New Zealander men understand the faux pas in using that term.
Men, wear black tie. It’s part of your culture.
Women, if the men resist, show him the evening gown you are wearing to the next ball and ask him how he’ll cope with his own embarrassment when he doesn’t rise to the occasion to match you. You don’t normally attend balls? Time to attend one a year, just to lift your soul.
Black tie. It’s the dress code of your culture, men.